Improvement in apparatus for manufacturing white lead



2 Sheets-Sheet 1.

H. HANNEN.

v Making White Lead. No. 19,771. Patented March 30511858.

' I l l L wU It "H U I 2 Sheets-Sheet 2.

H. HANNEN. Making White Lead.

I Patented March 30, 1858.

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I 7 H 1 z z a a? z, 5 a 1 J!- 5 ".f5 5 a 3 a UNITED STATES PATENT Trice.

HENRY HANNEN, OF DUBUQUE, IOXVA.

IMPROVEMENT IN APPARATUS FOR MANUFACTURING WHITE LEAD.

To all whom it may concern:

Be it known that I, HENRY I-IANNEN, ot" the city-and county of Dubuque, in the State of Iowa, have invented a certain new and useful Improvement in Apparatus for Manufacturing White Lead, of which the following is a 'full, clear, and exact description, reference being had to the accompanying drawings, making part of this specification, in which- Figure 1 represents a plan of an apparatus for manufacturing white lead constructed on my improved plan, the top of one chamber being removed in order to show the arrangement of the parts of the interior, the top and slats of another chamber for the support of the lead being also removed to exhibit the arrangement of pipes for the admission of steam and the vapors of acetic acid. Fig. 2 represents an end view of the same. Fig. 3 represents a vertical longitudinal section taken through the line 00 0c of Fig. 1; Fig. 4, a vertical transverse section taken through the line 00 0c of the same figure. Fig. 5 represents a vertical section of the gas-chamber and f urnace.

The nature of my improvement consists in so arranging and constructing an apparatus for manufacturing white lead that the lead may be exposed to the action of air, steam, acetic acid, and carbonic acid alternately and successively, which is found to be a much more preferable process (and for which I obtained a patent) than to expose the metal to the action of air, vapor, or hydrated acetic acid and carbonic acid conjointly.

To enable others skilled in the art to make, construct, and use my improved apparatus, I will now proceed to describe its parts in detail.

The chambers in which the lead is to be converted into the carbonate of lead are made of wood, and are arranged in two series A A, running parallelly with each other, the number of which will depend on the size and extent of the manufacture. In the inside and on the floor of each chamber are arranged two series of pipes a, which extend nearly to the sides of the chamber, and which are pierced with a number of holes-a row on each side and one on the top, or more, if deemed advisable-for the purpose of distributing steam through the chamber and the vapors of. acetic acid, which are conducted to them through a larger pipe B, arranged at the bottom of each chamber and which communicates on the outside at one end with the main pipe E from the boiler F, that contains the acetic acid, and at the other end with the steam-pipe 0, leading from the steam-boiler D. Each of these pipes B is provided with stop-cocks e and e, by means of which the vapors and steam may be admitted to the chamber or shut off, as desired.

Each chamber has near its top a branch pipe I leadinginto it, which communicates on the outside with the pipes G, through which the carbonic-acid gas is carried from the gas chamber or reservoir II. The branch pipes I are also provided with stop-cocks n for the purpose of regulating the admission of the carbonic-acid gas, which as it is admitted diffuses itself throughout the chamber, it having atendency to fall toward the bottom by virtue of its superior specific gravity. Into each of these chambers, commencingalittle above the pipes a, are arranged several series of slats b at suitable distances apart for the reception of the coils of lead, and upon which they are to be placed, and which are introduced into the chamber through a door J, made to fit with great exactness to prevent the escape of the gases. These doors are secured by means of cross-bars p, and are provided with panes of glass, there being others arranged in the rear side of each chamber to enable the attendants to watch the progress of the process. The chimneys c, which pass through the' center of each chamber, serve the purpose of diffusing the vapors and gasesequally throughout the chambers. The sides of these chimneys c, which are formed of wood or any other suitable material, are pierced with a number of holes for the admission of vapors and gases from the chamber, and the mouth of each chimney provided with avalve d. When the valvedis closed, the cold air on the outside, acting upon the walls of the chamber, draws the vapors toward them; but by opening the valve 01 a draft is immediately created in the chamber and the gases drawn toward its center. In the top of each chamber several apertures f are made, furnished with valves g, the object of which is to permit or to cut off the escape of gases and vapors, as may be required. At the sides of the chambers, near the bottom, are also pierced holes i, furnished with valves or stoppers Ifor the admission of air or the escape of gases.

The furnace K is provided with two chimneys, one L leadinginto the open air and the other M into the gas-chamber H, each furnished with a valve, so that when a fresh supply of fuel has been added to the furnace the chimney M, leading to the gas-reservoir, can be closed by its valve until all the smoke, &c., have been driven off through the chimney L leading to the atmosphere, after which the valve of the latter is closed and that of the otheropened for the admission of the carbonic acid evolved from the incandescent coals into the gas-chamber H.

From the foregoing description of the apparatus it will be apparent that the metal can be exposed to the action. of the diff rent agents employed for the purpose of converting it into white lead alternately and successively as by opening the stop-cocks e, communicating with the steanrpipes O, and closing the stopcocks e of the pipes E, carrying the vapors of acetic acid and the stop-cocks n of the gaspipes G, the steam will pass along the pipes B into the perforated pipes a, and then diffuse itself throughout the chambers. When a sufiiciently thick coating of oxide has been formed, the stop-cocks e are closed and the valves 9 opened for a short time to permit the escape of the steam, after which the stopcocks e are turned, when the vapor of the acetic acid will enter the pipe B and diffuse itself in like manner throughout the chambers. Afterasufficient time has been allowed for the formation of the subacetate of lead the stop-cocks e are closed and the valves g again opened to permit the vapor of acetic acid to escape, which done, the stop-cocks 'n of the pipes J are then opened, thus admitting the carbonic acid, which, as it falls to the bottom, diffuses itself throughout the chambers and decomposes the subacetate forming the carbonate of lead, after which it is in turn shut off and the valves 9 and stoppers or valves Z opened to permit its escape. During the process the valves (Z may be opened for a short time from time to time for the purpose of diffusing the vapors equally throughout the chambers, as before described.

In order to keep up a more regular temperature in the chambers during the process, a steam-chamber may be formed under the bottom of each, into which steam may be passed from the boiler in any suitable manner.

Having thus fully described my improvement, I claim- The pipe G with its branch pipes T and stopcocks n, the pipes O and E, and the diffusing pipes B and a, and their respective stop-cocks e and e, in combination with the valves oi'- fat 

